304Cu和430Cu抗菌不锈钢中富铜相的演化及其抗菌性能

Evolution of copper⁃rich phases and antibacterial properties of 304Cu and 430Cu antimicrobial stainless steels

添加适量的Cu制备了304Cu和430Cu抗菌不锈钢。借助XRD、OM和TEM,研究了不同退火温度对两种含Cu抗菌不锈钢组织及其抗菌性能的影响,并分析了富Cu相随退火温度的演化规律。结果表明,304Cu抗菌不锈钢的显微组织由不规则奥氏体构成,而430Cu抗菌不锈钢的显微组织均由多边形铁素体构成,局部存在异常长大的晶粒。在304Cu抗菌不锈钢中的富铜相呈圆形,且随着退火温度的升高,富铜相数量增加,尺寸增大,但退火温度超过850℃后,长大速率变缓。而在430Cu抗菌不锈钢中,富铜相的尺寸随着退火温度的升高而增大,退火温度达900℃时,形状由球形或椭球形变为杆状。经过850℃退火处理的两种试验钢均具有优异的抗菌性能,能够延缓与之接触的豆制品、大米饭腐败进程,还能在自身周围形成抑菌环境。

304Cu and 430Cu antibacterial stainless steels were prepared by adding appropriate amount of Cu.By means of XRD,OM and TEM,the effect of different annealing temperatures on microstructure and antibacterial properties of the two steels was investigated,and the evolution of Cu⁃rich phases was analyzed.The results show that the microstructure of the 430Cu stainless steel is mostly composed of polygonal ferrite,with a small amount abnormally grown grains distributed locally,while the microstructure of the 304Cu stainless steel is composed of irregular austenite.The copper⁃rich phases in the 304Cu antibacterial stainless steel is round in shape,the number of which increases and the size grows with the increase of annealing temperature,though the growth rate becomes slower when the annealing temperature exceeds 850℃.While in the 430Cu antibacterial stainless steel,the size of copper⁃rich phases grows with the annealing temperature rising,and the shape of copper⁃rich phase changes from spherical or ellipsoid to rod when the annealing temperature reaches 900℃.After annealing at 850℃,both the 304Cu and 430Cu stainless steels exhibit excellent antibacterial properties,which can delay the spoilage process of soybean products and rice in contact with it,and it can also form a bacteriostatic environment around itself.